Where the uke loses a bet with his friends, propositions a businessman, gets drugged, and stripped and placed on a roulette table where a number of men bet on his body parts to play with. Then gets initiated by said businessman, and then his friend comes over, and he finds out his friend had set him up, and the businessman was the onii-san he used to play with in the past. After that, both the businessman and the friend do the uke.

... ...

What am I reading? Seriously... But uh, all help will be much appreciated. Thank you!

Thank you! That's it... It's been bothering me that I couldn't figure out the manga.